Does higher samples and viewport mean a better quality of render?
The render samples are what impacts your final render, when you render with F12 or Render > Render Image / Render > Render Animation.  As a rule of thumb, more samples mean less noise in the render. The difference may not be as obvious as in Cycles, because Eeeve is doing rasterization and not  path tracing.

Eevee render with 16 samples



Eevee render with 64 samples



Close-up 16 samples



Close-up 64 samples



The viewport samples are for the preview in the viewport, when you choose Display Render Preview.